This section provides background information related to the present disclosure which is not necessarily prior art.
In the semiconductor industry, electronic devices are often produced by means of a deposition process (e.g., chemical vapor deposition (CVD), atomic layer deposition (ALD), etc.). Typically, a liquid or solid precursor is supplied, for example, in a container through which a carrier gas, such as nitrogen or hydrogen, may be moved via a dip pipe so that the gas becomes saturated with the precursor. The carrier gas/precursor vapor mixture is then passed at a controlled rate into an epitaxial reactor. Such systems are used in the production of both silicon and compound semiconductors. It is important that the concentration of the chemical in the vapor phase be extremely stable. Channeling and non-uniform surfaces provided by conventional single-use type systems can lead to variable vaporization of the precursors, causing fluctuations in the gas/precursor concentrations. Such fluctuations are adverse to the deposition process. This is particularly noticeable with solid precursors, such as trimethylindium (TMI).
In metalorganic chemical vapor deposition (MOCVD) systems, a steady, controllable flux of precursor into the reaction chamber is important when fabricating highly complex device structures. Typically, simple delivery system designs are employed to perform this task with the carrier gas flow and source temperature control being able to provide a suitably stable system. However, increasing volume demands, for example, placed on MOCVD equipment have necessitated increased flows and/or larger systems. These typical delivery system designs are no longer suitable to meet these requirements.